As imaging technologies develop, imaging devices such as copiers, printers, fax machines, and word processors are widely used. Such imaging devices include an imaging cartridge for containing ink or toner (both hereinafter referred to as consumable), which is convenient for a user to replace. Usually, an unused imaging cartridge may store a certain volume of consumable. When the consumable in the imaging cartridge is exhausted, it is necessary to replace the imaging cartridge in time.
In order to remind the user of replacing the imaging cartridge in time and avoiding degradation of the imaging quality and damages to the imaging device caused by the continuous printing after the consumable is exhausted, more and more imaging cartridges are equipped with imaging cartridge chips. The imaging device may determine consumable volume information (mainly indicated by remaining consumable volume information or consumable consumption information) in the imaging cartridge and store the consumable volume information in the chip.
During an imaging operation, the imaging device reads the consumable volume information from the chip and displays the consumable volume information to the user in a relatively intuitive way, for example, in the form of a percentage or a progress bar, so as to allow the user to know currently remaining consumable volume in the imaging cartridge and remind the user of replacing imaging cartridge in time when the remaining consumable volume in the imaging cartridge is relatively few. When the consumable in the imaging cartridge is about to be exhausted, the imaging device may “lock” the chip to prevent the imaging device from continuing imaging operation, avoiding degradation of the imaging quality that may lead to the waste of paper and consumable, and also avoiding damages to the imaging device when the consumable is insufficient.
In order to accurately predict when the imaging cartridge needs to be replaced, the consumable volume information should have a high accuracy to ensure effectively that the imaging cartridge does not contain a relatively large volume of remaining consumable and avoid waste of consumable when the imaging device “locks” the chip. From the perspective of using consumable economically and reducing costs as much as possible, the user usually purchases a new imaging cartridge for replacement only when the user discovers, by observing the percentage or the progress bar of the imaging device, that the consumable in the imaging cartridge is nearly exhausted.
Some of the existing imaging devices may be compatible with multiple types of imaging cartridges. Different types of imaging cartridges may differ greatly in the number of pages that can be imaged. If the remaining consumable volume is reminded using the same standard, it is easy for the user to make a misjudgment on the number of printable pages when the accuracy of the consumable volume information is too high.
For example, an imaging device may indicate a remaining consumable volume in the imaging cartridge by a percentage ranging from 0 to 100%. The accuracy of the remaining consumable volume is 1%. For an imaging cartridge having a number of printable page of 800, when the imaging device displays that only one cell in the progress bar indicating the remaining consumable volume information remains (corresponding to 5% of the full consumable volume), the number of remaining printable pages is 40. It may be timely for the user to purchase a new consumable cartridge for replacement at that moment. For an imaging cartridge having a number of printable pages of 200, when the imaging device displays that only one cell in the progress bar indicating the remaining consumable volume information remains (corresponding to 5% of the full consumable volume), the number of remaining printable pages is only 10, A printing task printing a large number of pages may exhaust the consumable. So the misjudgment on the number of remaining printable pages by the user may lead to the failure to have a new imaging cartridge ready timely. For an imaging cartridge having a number of printable pages of 2,000, when the imaging device displays that only one cell in the progress bar indicating the remaining consumable volume information remains (corresponding to 5% of the full consumable volume), the number of remaining printable pages is 100. That figure corresponds to 50% of consumable volume of a small volume imaging cartridge. At that moment, a reminder to the user may lead to a premature replacement of the previous imaging cartridge by the user, which may cause the waste of consumable.
During each imaging operation, the imaging device writes new consumable volume information into the imaging cartridge chip to update consumable volume information previously stored in the imaging cartridge chip. The higher accuracy the consumable volume information is, the larger the byte is. When the power supply to the imaging device is interrupted suddenly, it may be likely to occur that the consumable volume information is unable to be written into the imaging cartridge chip completely, which may cause the writing error or loss of consumable volume information.